The microstructures and anti-corrosion behavior of the thermal sprayed Hastelloy C276 coating on substrate of Q235 steel

Hastelloy C276 coating was prepared on the substrate of Q235 steel by arc thermal spraying process. The microstructure, microhardness, thermal shock resistance and anti-corrosion of the coating were investigated. The coating exhibits a layered buildup structure with some pores and unmelted particles appearing. There is a distinct and rough interface between the coating and the substrate which increases the contact area between the coating and the substrate. The coating and the substrate were meshed to each other in the boundary, showing a strong bonding. The coating exhibited a strong thermal shock resistance with the substrate of Q235 steel at 600 °C. The microhardness of the surface of the coating is much higher than the microhardness of the surface of the substrate. Uniform corrosion method of laboratory semi-immersion test was used to test the corrosion resistance of C276 coating. The coating exhibited good corrosion resistance in concentrated HCl with a concentration of 36.5%.